CA1275121A - Platform weighing apparatus and method for producing thereof - Google Patents
Platform weighing apparatus and method for producing thereofInfo
- Publication number
- CA1275121A CA1275121A CA000529539A CA529539A CA1275121A CA 1275121 A CA1275121 A CA 1275121A CA 000529539 A CA000529539 A CA 000529539A CA 529539 A CA529539 A CA 529539A CA 1275121 A CA1275121 A CA 1275121A
- Authority
- CA
- Canada
- Prior art keywords
- platform
- base frame
- concrete
- shuttering
- force measuring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01G—WEIGHING
- G01G19/00—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups
- G01G19/02—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups for weighing wheeled or rolling bodies, e.g. vehicles
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01G—WEIGHING
- G01G19/00—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups
- G01G19/44—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups for weighing persons
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01G—WEIGHING
- G01G21/00—Details of weighing apparatus
- G01G21/22—Weigh pans or other weighing receptacles; Weighing platforms
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Moulds, Cores, Or Mandrels (AREA)
- Refuge Islands, Traffic Blockers, Or Guard Fence (AREA)
Abstract
Abstract:
A platform weighing apparatus is at least partially made of polymeric concrete. With one embodiment a lost self-supporting shuttering made of polymeric concrete is used for forming the platform of the weighing apparatus and a base frame is made of polymeric concrete. With another embodiment the platform is structured with cavities and made essentially of polymeric con-crete. The method according to the invention permits moulding of the shuttering or the complete platform at a manufacturing site with easy transportation and assembly at an operational site.
A platform weighing apparatus is at least partially made of polymeric concrete. With one embodiment a lost self-supporting shuttering made of polymeric concrete is used for forming the platform of the weighing apparatus and a base frame is made of polymeric concrete. With another embodiment the platform is structured with cavities and made essentially of polymeric con-crete. The method according to the invention permits moulding of the shuttering or the complete platform at a manufacturing site with easy transportation and assembly at an operational site.
Description
Ti-tle:
PLATFORM WEIGHING APPARATUS AND METHOD FOR PRODUCING THEREOF
Technical Field:
The present invention relates to a platform weighing apparatus and a method of producing -thereo-F by moulding or casting. The platform weighing apparatuses of the invention may be used for high loads, in particular for truck weighing systems, or smaller loads, exemplary as bathroom scales.
Background Ar-t:
The European Pa-tent Application Publication 0097734 discloses a truck weighing apparatus having a platform made of usual con-crete, the platform being supported by force measuring elements in a pit made of usual concrete and forming a base the top of which being provided wi-th a circumferential Frame the top sur-face of which flushing with the top surface of the platform. The platform and the -frame are made at the operational site by using a lost, self-supporting shuttering or form for -the platform.
The form consists of a plurality of form elements made of steel sheets which are fixedly secured to each other by screws or rivets. Base members for supporting the force measuring elements may be casted separa-tely or simultaneously wi-th the platform.
The production and assembly of the self-supporting form using steel sheets are time-consuming and expensive in respect o-f the material used, since each s-teel sheet has to be formed indivi-dually and secured to another steel sheet. The concrete used as restricted in its tensile s-trength, such that heavy rein-forcemen-ts and a consi~erable thickness is necessary when the apparatus is used as a -truck weighing appara-tus. The base member in the pi-t must have an exac-tly defined form and high-quality concrete mus-t be used therefore. Also, considerable care is necessary when casting -the frame of -the base member. There is a rela-tively wide gap between the pla-tform and -the frame per-mitting pene-tration of dirt and humidity into the pit. More-over, specific bumpers made o-f me-tal are provided to restrict a lateral movement of the platform within the ba'se member. The force measuring elemen-ts arranged between the pla-tform and the bottom of the base member can be accessed from the pit only necessitatin~ a separate entrance thereto.
The European Patent Application Publica-tion 0108164 discloses a platform weighing apparatus using a platform made o-f steel provided with openings for inserting the Force measuring ele-ments.
The US Patent No. 4,549,622 discloses a platform weighing apparatus the platform of which is made of concrete and is supported on shear beam -type load cells arranged at each corner of the platform. Support means -for the platform and the load cells are o-f the self-restoring type absorbing any lateral forces.
At least a dozen years ago another type of concrete has become known which is called ~polymeric concrete". This material uses synthetic resins as a binder for filler materials, as sand.
Polymeric concrete has a far better tensile strength than usual concrete and an excellent resistancy against chemical substances.
Up to now this material has been used in replacement of usual concrete for plates and ~ubes and for support bases of tooling machines. However, up to now polymeric concrete was not used in connection with weighing systems, apparently because of the quite different characteristics in respect of thermal expansion and costs.
Summary of the Invention:
It is an object of the present invention to provide a platform ~ Z75~2~
weighing apparatus manufactured with considerably reduced e-fforts in respect o-f time and cos-ts.
It is another object of the present invention to provide a plat-form weighing apparatus which qui-te simply mav be produced a~ an operational site.
It is a further object of the present invention to provide a platform weighing appara-tus being highly resistan-t against chemical substances.
It is a further object o-f the present invention to provide a platform weighing apparatus which may be pre-fabricated in a plant and which is easily transpor-table to an operational site and easy to put in-to function.
It is a further object of the present invention to provide a method for manufacturing a platform weighing system which allows a simple and fast fabrication at an operational site using pre-fabricated elements.
It is a still further object of the present invention to pro-vide a platforrn weighing apparatus having an extremely low overall height.
It is a still further object of the present invention to pro-vide a pla-tform weighing apparatus without any mechanical link-age and without any burnpers between -the pla-tform and the base member.
According to the invention a heavy duty weighing apparatus for trucks, equipment and the like inc1udes a pla-tform mountable in a ground pit on force measuring elemen-ts resting on concrete support means, -the plat-form co!.1prising a lost self-supporting shu-ttering pre-fabricated of polymeric concrete filled, at an opera-tional site, with cement concrete.
l2~
According to another aspect of the invention a method of manufacturing a heavy duty platform weighing apparatus comprises the steps pre-fabricating a shuttering for said platform by moulding of polymeric concrete material at a manufacturing site: transporting said shuttering to an operational site; and connecting said platform by filling said shuttering with cement concrete.
According to another aspect of the invention a platform weighing apparatus comprises a platform structured by including cavities and pra-fabricating of polymeric concrete by moulding; a base means; and force measuring elements arranged between said platform and said base means.
According to another aspect, an embodiment of the invention is a heavy duty weighing apparatus including a platform mountable in a ground pit and comprising a base frame insertable into the ground pit for loosely accommodating the platform, the base frame being pre-fabricated of polymeric concrete and having an essentially horizontal top face surface flush with a force receiving surface of the platform and lower horizontal sections extending inwards in the ground pit for supporting force measuring elements on which the platform rests.
According to another aspect, an embodiment of the invention is a method for manufacturing a platform weighing apparatus comprising the steps: preparing a mould according to the outer contours of a platform at a manufacturing site, placing form bodies into the mould corresponding to cavities to be formed in the platform, moulding the platform by filling-in of polymeric concrete into the mould, and removing the platform after solidification of the polymeric concrete from the mould.
3~
- ~a -Brief Description of the Drawinqs:
Fig. 1 is a perspective view, partially in section, of a first embodiment of a truck weighing apparatus according to the invention;
Fig. 2 is a perspective view similar to that of Fig. 1 of a modified embodiment using a different type of force measuring element;
Fig. 3 is an enlarged sectional view oE an elastic connection between a base frame and a platform of the embodiments of Figs. 1 and 2;
Fig. 4 is a perspective view similar to that of Fig. 1 of a further embodiment of a truck-wPighing apparatus according to the invention; and Figs. 5 are sectional views of embodiments of different to 9 type of platform weighing apparatuses according to the invention.
Description of Preferred Embodiments of the Invention:
Figs. 1 to 4 show embodiments of a first type of platform weighing apparatus according to the invention particularly adapted to be used in truck weighing systems.
J 1 217~
Fig. 1 shows a first embodimen-t of a plat-form-type weighing apparatus, especially adapted as a vehicle or truck weighing apparatus. A platform 10 loosely fits into a pit essentially de-fined by a base frame 34. This base frame 34 comprises a lower horizontal par-t 34a in the inner region and a part 34b extending upwards and preferably outwards from the lower hori-zontal part 34a. At the toP the par-t 34b ends in a prefer-ably broadend head ledge 34c having a flat upper horizontal face surface. The base frame may be reinforced by having the free edge of the horizontal part 34a bent downwards.
According -to -the invention the pla-tform 10 comprises a sel-F-supporting shuttering or form 12 having a peripheral side wall 20 -the outer surface oF which is adapted to the inclination of the par-t 34b o-f the base -Frame 34.
According to the invention -the selfsupporting form 12 and prefer-ably also the base frame 34 are made o-f so-called "polymeric concrete~. This ma-terial is known per se and comprises 3 to 5%
of a synthetic resine exemplary acry~ic resin and binding filler materials, mainly sand (SiO2) having a grain size of 0 to 8mms.
This polymeric concrete may further have embedded glass,steel and/or carbon fibres. If desired, a reinforcement in the form of a mat of steel or fibres may be embedcled.
In contrast to the known arrangement mentioned above such a lost self supporting polymeric concrete form 12 may be produced in a plant in large quantities by simply casting in an appropriate mould. Due to the relatively low weight it is easy to place it on a truck and to transpor-t it to the si te of operation. The same is true for the base frame 34.
At the operation site there is no need for a shuttering or form-work for forming the pit, at it is necessary for known weighing apparatuses. Rather, after digsin~ ar)dppropriale pit~ only in ~ 2~
those regions where the platform 10 is supported by force measuring elemen-ts 16 supporting beams 38 are provided in a non-freezing depth made oF usual lean concrete. Preferably, -the ground is then covered with a -thin plane layer 44 of lean concrete as well. ~rhe pit has such a size -that -there is enough peripheral space for filling in -further lean concre~ 40 after inserting the base frame 34, the horizontal top surface of the part 34c of the base Frame flushing with the road sur-face. Preferably, the ground around the pit is compacted be-fore these s-teps. It should be noted tha-t the pit is formed by the layer 44 and the base frarne 34 only. By filling in the lean concrete 40 penetrating into the region below the hori-zon-tal part 34a of the base frame 34 the apparatus obtains -the desired stability.
In a similar manner,the pla-tform 10 is comple-ted at the oper-a-tional site by filling -the self-supporting form 12 o-F poly-meric concrete wi-th common concrete as used For weighing plat-forms before, such that a plane top surface 50 is obtained. The bottom of the form 12 may be provided with reinforced longi-tudinal beams extending in parallel to the longitudinal edges of the platform 10 whilst the middle region may have a lower thickness as may be seen from Figs. 1 and 2.
The arrangement of the ,orce measuring elements 16 at the plat-form ends and at the junctions of platform elements pu-t to-gether (as it will be explained later on) is of particular im-portance -for the invention. As may be seen from Fig. 1 the force measuring elements 16 are housed in s-teel cylinder 22 fixedly cast into a polymeric concrete column 18 forming an integrated part of the form 12.
The upper end of the steel cylinder 22 may be provided with an inner threading 32 into which a force introduction pla-te 26 provided with an outer threading may be screwed in. With the '75~
embodiment according to Fig. 1 the force measuring device 30 of the force measuring elemen-t 16 is supported by the inner region of the horizontal part 34a of the base frame 34. Thus any force exer-ted to the top surface 50 of the platform 10 is transmitted from the force introduction plate 26 to the force measuring device 30 by means of known restoring pins or self-errecting rolling bodies 28. The radii of the curved face sur-faces of the restoring pins 28 are selected relatively large.
As known in the weighing field these face surfaces engage spherical recesses having an even larger radii of curvature.
As may seen from Figs. 1 and 2, the force measuring element 16 may be inserted into the platform 10 from the topside thereof which facilita-tes maintainance and exchange of the force measu-ring elements 16. Housing the force measuring devices 30 in the polymeric concrete columns 18 and in particular providing the steel cylinder 28 results in a remarkably small overall height of the apparatus, since between the bottom side of the form 12 and the lean concrete layer 44 only a small gap is re-quired.
As force measuring device 30 usual devices are applicable as piezoresistive force measuring cells.
As a modification of the embodiment of Fig. 1, Fig. 2 shows a she~rin~-t~p~ s'~rain gauge 82 used as a force measur-ing element, the force introduction being achieved by a known pan/edge bearing.
It should be noted,that the force introduction plate 26 may be replaced by a differently formed plate being inserted into an appropriate opening at the top side of the platform 10 with the only requirement tha-t such a plate is immovably secured to the platform 10. Also, the steel cylinder 22 may be replaced by an insert 84 frustro -conicaily; opened in downward direction.
Such an insert 84 may be formed at its top end with a threaded 75~
rim of a larger diame-ter. Such a design has the same Function as the s-teel cylinder 22 which is provided with laterally extending flanges which ensure the immovable position thereoF.
According to a further aspect of the invention,a gap 52 (Figs. 2 and 3) between the upper edge of the pla-tform lû and -the upper inner edge o-F the base frame 34 is covered by a tight sealing.
According -to the invention this gap 52 is closed by a cover strip 60 made of elastomeric material, exemplary having a Shore Value in the range of 40 to 60. Preferably, the cover strip is made of rubber or synthetic material as commonly used for conveyor belts.
The cover s-trip 60 may have embedded a band or net of steel or similar material as a reinforcement. The width of the cover strip 60 is such -that it may be conveniently secured both to the platform lO and the base frame 34. Fig. 3 illustrates details of an exemplary fixing. The peripherally ex-tending cover strip 60 is fi-tted in appropria-te recesses 62 and 64 at the inner upper edge of the part 34c of the base frame 30 and the outer upper edge 20 of the form 12. By means of securing ledges or plates 66 and 68 arranged along the cover strip 60 and partially over-lYillS it , the cover strip 60 is clamped to -the base frame part 34c and the upper edge 20 of the form 12. Such a clamping may be accomplished by screws 70 screwed into threaded inserts arranged in appropriate distances in the mould for the base frame 34 and the form 12, respectively. The threaded inserts are designated with the reference numeral 72. Such a clamping ensures that no humidity and dirt may penetrate in-to the interior of the weighing apparatus. On the other hand, the cover strip 60 connects the base -frame 34 and the -form 12 elastically -to such an extent that the cover strip ac-ts as a horizontal guidance of the platform 10. Thus, no bumpers are necessary. Furthermore, the use of such a clam,ped cover strip 60 reduces the sa-fety distance between the platform lO and -the base frame 34 considerably.
Truck weighing apparatuses having an extraordinary leng-th may ~ Z'~5~
- os -use a platform consisting of several modules which are connected with each other at step-like formed engaging sur-faces,elastomeric ma-terial 80, exemplary silicone rubber,-filling any gap -there-be-tween The overall arrangement is kept toge-ther by the peri-pheral cover strip 60.
To sum up, a preferred method of manufacturing the platform weighing apparatus according to the invention is as follows:
1. Casting or moulding the lost self-supporting form 12 and the base frame 34 of polymeric concrete material at a plant;
PLATFORM WEIGHING APPARATUS AND METHOD FOR PRODUCING THEREOF
Technical Field:
The present invention relates to a platform weighing apparatus and a method of producing -thereo-F by moulding or casting. The platform weighing apparatuses of the invention may be used for high loads, in particular for truck weighing systems, or smaller loads, exemplary as bathroom scales.
Background Ar-t:
The European Pa-tent Application Publication 0097734 discloses a truck weighing apparatus having a platform made of usual con-crete, the platform being supported by force measuring elements in a pit made of usual concrete and forming a base the top of which being provided wi-th a circumferential Frame the top sur-face of which flushing with the top surface of the platform. The platform and the -frame are made at the operational site by using a lost, self-supporting shuttering or form for -the platform.
The form consists of a plurality of form elements made of steel sheets which are fixedly secured to each other by screws or rivets. Base members for supporting the force measuring elements may be casted separa-tely or simultaneously wi-th the platform.
The production and assembly of the self-supporting form using steel sheets are time-consuming and expensive in respect o-f the material used, since each s-teel sheet has to be formed indivi-dually and secured to another steel sheet. The concrete used as restricted in its tensile s-trength, such that heavy rein-forcemen-ts and a consi~erable thickness is necessary when the apparatus is used as a -truck weighing appara-tus. The base member in the pi-t must have an exac-tly defined form and high-quality concrete mus-t be used therefore. Also, considerable care is necessary when casting -the frame of -the base member. There is a rela-tively wide gap between the pla-tform and -the frame per-mitting pene-tration of dirt and humidity into the pit. More-over, specific bumpers made o-f me-tal are provided to restrict a lateral movement of the platform within the ba'se member. The force measuring elemen-ts arranged between the pla-tform and the bottom of the base member can be accessed from the pit only necessitatin~ a separate entrance thereto.
The European Patent Application Publica-tion 0108164 discloses a platform weighing apparatus using a platform made o-f steel provided with openings for inserting the Force measuring ele-ments.
The US Patent No. 4,549,622 discloses a platform weighing apparatus the platform of which is made of concrete and is supported on shear beam -type load cells arranged at each corner of the platform. Support means -for the platform and the load cells are o-f the self-restoring type absorbing any lateral forces.
At least a dozen years ago another type of concrete has become known which is called ~polymeric concrete". This material uses synthetic resins as a binder for filler materials, as sand.
Polymeric concrete has a far better tensile strength than usual concrete and an excellent resistancy against chemical substances.
Up to now this material has been used in replacement of usual concrete for plates and ~ubes and for support bases of tooling machines. However, up to now polymeric concrete was not used in connection with weighing systems, apparently because of the quite different characteristics in respect of thermal expansion and costs.
Summary of the Invention:
It is an object of the present invention to provide a platform ~ Z75~2~
weighing apparatus manufactured with considerably reduced e-fforts in respect o-f time and cos-ts.
It is another object of the present invention to provide a plat-form weighing apparatus which qui-te simply mav be produced a~ an operational site.
It is a further object of the present invention to provide a platform weighing appara-tus being highly resistan-t against chemical substances.
It is a further object o-f the present invention to provide a platform weighing apparatus which may be pre-fabricated in a plant and which is easily transpor-table to an operational site and easy to put in-to function.
It is a further object of the present invention to provide a method for manufacturing a platform weighing system which allows a simple and fast fabrication at an operational site using pre-fabricated elements.
It is a still further object of the present invention to pro-vide a platforrn weighing apparatus having an extremely low overall height.
It is a still further object of the present invention to pro-vide a pla-tform weighing apparatus without any mechanical link-age and without any burnpers between -the pla-tform and the base member.
According to the invention a heavy duty weighing apparatus for trucks, equipment and the like inc1udes a pla-tform mountable in a ground pit on force measuring elemen-ts resting on concrete support means, -the plat-form co!.1prising a lost self-supporting shu-ttering pre-fabricated of polymeric concrete filled, at an opera-tional site, with cement concrete.
l2~
According to another aspect of the invention a method of manufacturing a heavy duty platform weighing apparatus comprises the steps pre-fabricating a shuttering for said platform by moulding of polymeric concrete material at a manufacturing site: transporting said shuttering to an operational site; and connecting said platform by filling said shuttering with cement concrete.
According to another aspect of the invention a platform weighing apparatus comprises a platform structured by including cavities and pra-fabricating of polymeric concrete by moulding; a base means; and force measuring elements arranged between said platform and said base means.
According to another aspect, an embodiment of the invention is a heavy duty weighing apparatus including a platform mountable in a ground pit and comprising a base frame insertable into the ground pit for loosely accommodating the platform, the base frame being pre-fabricated of polymeric concrete and having an essentially horizontal top face surface flush with a force receiving surface of the platform and lower horizontal sections extending inwards in the ground pit for supporting force measuring elements on which the platform rests.
According to another aspect, an embodiment of the invention is a method for manufacturing a platform weighing apparatus comprising the steps: preparing a mould according to the outer contours of a platform at a manufacturing site, placing form bodies into the mould corresponding to cavities to be formed in the platform, moulding the platform by filling-in of polymeric concrete into the mould, and removing the platform after solidification of the polymeric concrete from the mould.
3~
- ~a -Brief Description of the Drawinqs:
Fig. 1 is a perspective view, partially in section, of a first embodiment of a truck weighing apparatus according to the invention;
Fig. 2 is a perspective view similar to that of Fig. 1 of a modified embodiment using a different type of force measuring element;
Fig. 3 is an enlarged sectional view oE an elastic connection between a base frame and a platform of the embodiments of Figs. 1 and 2;
Fig. 4 is a perspective view similar to that of Fig. 1 of a further embodiment of a truck-wPighing apparatus according to the invention; and Figs. 5 are sectional views of embodiments of different to 9 type of platform weighing apparatuses according to the invention.
Description of Preferred Embodiments of the Invention:
Figs. 1 to 4 show embodiments of a first type of platform weighing apparatus according to the invention particularly adapted to be used in truck weighing systems.
J 1 217~
Fig. 1 shows a first embodimen-t of a plat-form-type weighing apparatus, especially adapted as a vehicle or truck weighing apparatus. A platform 10 loosely fits into a pit essentially de-fined by a base frame 34. This base frame 34 comprises a lower horizontal par-t 34a in the inner region and a part 34b extending upwards and preferably outwards from the lower hori-zontal part 34a. At the toP the par-t 34b ends in a prefer-ably broadend head ledge 34c having a flat upper horizontal face surface. The base frame may be reinforced by having the free edge of the horizontal part 34a bent downwards.
According -to -the invention the pla-tform 10 comprises a sel-F-supporting shuttering or form 12 having a peripheral side wall 20 -the outer surface oF which is adapted to the inclination of the par-t 34b o-f the base -Frame 34.
According to the invention -the selfsupporting form 12 and prefer-ably also the base frame 34 are made o-f so-called "polymeric concrete~. This ma-terial is known per se and comprises 3 to 5%
of a synthetic resine exemplary acry~ic resin and binding filler materials, mainly sand (SiO2) having a grain size of 0 to 8mms.
This polymeric concrete may further have embedded glass,steel and/or carbon fibres. If desired, a reinforcement in the form of a mat of steel or fibres may be embedcled.
In contrast to the known arrangement mentioned above such a lost self supporting polymeric concrete form 12 may be produced in a plant in large quantities by simply casting in an appropriate mould. Due to the relatively low weight it is easy to place it on a truck and to transpor-t it to the si te of operation. The same is true for the base frame 34.
At the operation site there is no need for a shuttering or form-work for forming the pit, at it is necessary for known weighing apparatuses. Rather, after digsin~ ar)dppropriale pit~ only in ~ 2~
those regions where the platform 10 is supported by force measuring elemen-ts 16 supporting beams 38 are provided in a non-freezing depth made oF usual lean concrete. Preferably, -the ground is then covered with a -thin plane layer 44 of lean concrete as well. ~rhe pit has such a size -that -there is enough peripheral space for filling in -further lean concre~ 40 after inserting the base frame 34, the horizontal top surface of the part 34c of the base Frame flushing with the road sur-face. Preferably, the ground around the pit is compacted be-fore these s-teps. It should be noted tha-t the pit is formed by the layer 44 and the base frarne 34 only. By filling in the lean concrete 40 penetrating into the region below the hori-zon-tal part 34a of the base frame 34 the apparatus obtains -the desired stability.
In a similar manner,the pla-tform 10 is comple-ted at the oper-a-tional site by filling -the self-supporting form 12 o-F poly-meric concrete wi-th common concrete as used For weighing plat-forms before, such that a plane top surface 50 is obtained. The bottom of the form 12 may be provided with reinforced longi-tudinal beams extending in parallel to the longitudinal edges of the platform 10 whilst the middle region may have a lower thickness as may be seen from Figs. 1 and 2.
The arrangement of the ,orce measuring elements 16 at the plat-form ends and at the junctions of platform elements pu-t to-gether (as it will be explained later on) is of particular im-portance -for the invention. As may be seen from Fig. 1 the force measuring elements 16 are housed in s-teel cylinder 22 fixedly cast into a polymeric concrete column 18 forming an integrated part of the form 12.
The upper end of the steel cylinder 22 may be provided with an inner threading 32 into which a force introduction pla-te 26 provided with an outer threading may be screwed in. With the '75~
embodiment according to Fig. 1 the force measuring device 30 of the force measuring elemen-t 16 is supported by the inner region of the horizontal part 34a of the base frame 34. Thus any force exer-ted to the top surface 50 of the platform 10 is transmitted from the force introduction plate 26 to the force measuring device 30 by means of known restoring pins or self-errecting rolling bodies 28. The radii of the curved face sur-faces of the restoring pins 28 are selected relatively large.
As known in the weighing field these face surfaces engage spherical recesses having an even larger radii of curvature.
As may seen from Figs. 1 and 2, the force measuring element 16 may be inserted into the platform 10 from the topside thereof which facilita-tes maintainance and exchange of the force measu-ring elements 16. Housing the force measuring devices 30 in the polymeric concrete columns 18 and in particular providing the steel cylinder 28 results in a remarkably small overall height of the apparatus, since between the bottom side of the form 12 and the lean concrete layer 44 only a small gap is re-quired.
As force measuring device 30 usual devices are applicable as piezoresistive force measuring cells.
As a modification of the embodiment of Fig. 1, Fig. 2 shows a she~rin~-t~p~ s'~rain gauge 82 used as a force measur-ing element, the force introduction being achieved by a known pan/edge bearing.
It should be noted,that the force introduction plate 26 may be replaced by a differently formed plate being inserted into an appropriate opening at the top side of the platform 10 with the only requirement tha-t such a plate is immovably secured to the platform 10. Also, the steel cylinder 22 may be replaced by an insert 84 frustro -conicaily; opened in downward direction.
Such an insert 84 may be formed at its top end with a threaded 75~
rim of a larger diame-ter. Such a design has the same Function as the s-teel cylinder 22 which is provided with laterally extending flanges which ensure the immovable position thereoF.
According to a further aspect of the invention,a gap 52 (Figs. 2 and 3) between the upper edge of the pla-tform lû and -the upper inner edge o-F the base frame 34 is covered by a tight sealing.
According -to the invention this gap 52 is closed by a cover strip 60 made of elastomeric material, exemplary having a Shore Value in the range of 40 to 60. Preferably, the cover strip is made of rubber or synthetic material as commonly used for conveyor belts.
The cover s-trip 60 may have embedded a band or net of steel or similar material as a reinforcement. The width of the cover strip 60 is such -that it may be conveniently secured both to the platform lO and the base frame 34. Fig. 3 illustrates details of an exemplary fixing. The peripherally ex-tending cover strip 60 is fi-tted in appropria-te recesses 62 and 64 at the inner upper edge of the part 34c of the base frame 30 and the outer upper edge 20 of the form 12. By means of securing ledges or plates 66 and 68 arranged along the cover strip 60 and partially over-lYillS it , the cover strip 60 is clamped to -the base frame part 34c and the upper edge 20 of the form 12. Such a clamping may be accomplished by screws 70 screwed into threaded inserts arranged in appropriate distances in the mould for the base frame 34 and the form 12, respectively. The threaded inserts are designated with the reference numeral 72. Such a clamping ensures that no humidity and dirt may penetrate in-to the interior of the weighing apparatus. On the other hand, the cover strip 60 connects the base -frame 34 and the -form 12 elastically -to such an extent that the cover strip ac-ts as a horizontal guidance of the platform 10. Thus, no bumpers are necessary. Furthermore, the use of such a clam,ped cover strip 60 reduces the sa-fety distance between the platform lO and -the base frame 34 considerably.
Truck weighing apparatuses having an extraordinary leng-th may ~ Z'~5~
- os -use a platform consisting of several modules which are connected with each other at step-like formed engaging sur-faces,elastomeric ma-terial 80, exemplary silicone rubber,-filling any gap -there-be-tween The overall arrangement is kept toge-ther by the peri-pheral cover strip 60.
To sum up, a preferred method of manufacturing the platform weighing apparatus according to the invention is as follows:
1. Casting or moulding the lost self-supporting form 12 and the base frame 34 of polymeric concrete material at a plant;
2. digging out a suitable pit;
3. producing in the pi-t beams 38 of lean common concrete and providing a lean concre-te layer 44 on the pit bo-ttom;
4. inserting -the base frame 34 into the pit, if desired after pressing a~ jacent soi l;
5. inserting -the form 12 into the base frame 34 together with arranging the force measuring elements 16 in the form 12;
6. securing the cover s-trip 60 at the base frame 34 and the form 12; and
7. filling the space between the rim of -the pit and the exterior of the base frame 34 with lean concre-te 40 and filling the form 12 with common concrete.
Even if the base frame 34 and the pit is produced in the usual way there are s-till advantages in using a pre-produced lost self-supporting form consis-ting of polymeric concre-te. Independently, the provision and clamping of the cover strip 60 is of importance for the platform weighing apparatus according to the invention, serving both as a sealing and as a bumper. Also, inserting the force measuring element from the top of the platform is extremely useful, since it does no more require any access to the space below the platform 10 resulting in an ex-tremely fla-t arrangement with an overall height in the order of 200 to 500 mms.
I-t should be noted, that the cover strip 60 replaces the complex .
S~2~.
mechanical linkage between the platform 10 and base frame 34 which again contributes to the reduction of -the overall height of the apparatus. Method step 7 indicated above enables the transport of -the base frame 34 having inserted thereto the form 12 clamped to the base frame 34 by the cover strip 60 as a unit.
The platform 10 may then be formed by filling usual concrete in-to the form 12 simultaneously with fixing the base frame 3~ into the pit by filling any spaces therebetween with lean conc~ete 40.
The cover strip 60 advantageously prevents any penetration of concrete into the peripheral gap 52.
The material called ~polymeric concrete" before is also known as polymeric casting material. In this connection it is referred to the firm publication KID-INF0 K.I.D. Impragniertechnik GmbH, Georgenstrasse 8, D-8018 Grafing, West-Germany. Polymeric syn-thetic materials which may be used for polymeric concrete are exemplary epoxy resirls (EP)s m~tl1yl-1etacry1a~e (,~1ilA) resin and unsaturated polyester resin (UP) or mixtures thereof.
Filler materials are prefereably quartz or chalk powders, quartzite or crushed granite. Furthermore, glassor preferably carbon fibres may be use. Also, other filler materials may be used as long as they do not undergo any essential chemical reaction with the resin and as long they are dry. It should be noted,~that the resins used for the polymeric concrete harden at ambient tempe-ratures. The hardening is initiated by suitable known agents and is completed in a time range between a few minutes and several t , hours. Since the method of providing moulds for moulding and casting polymeric synthetic material containing filler materials for the production of polymeric concrete is very similar to the preparation of forms for metal casting many measures used in the latter field are applicable for casting polymeriG concrete with the additional advantage of hardening at ambient temperatures, such that considerations of high temperatures are eliminated.
Polymeric concrete may be provided with appropriate reinforcements which may project above the surface of the polymeric concrete into ~ ~7S~
the interior of the form 12 Fig. 4 shows an embodimen-t o-f the platform weighing apparatus according -to the inven-tion wi-th the improvement tha-t in addi-tion -the -the base frame and the form 12 a sealing ~is in-tegrated into the form 12 again made of polymeric concre-te. This resul-ts in an increased s-tiffness of the form and a highly resistant pavemen-t against chemical and mechanical influences. The cement concre-te is filled-in through openings 92 whils-t further open-ings 94 spaced from the openings 92 and having preferably a smaller diameter serve as air ou-tlets and for monitoring the complete filling of -the form with concrete. Wi-th such a ceiling 92 no fine -treatment of -the top surface of the platform is necessary and -the shape of the platform is exactly defined by the form having the ceiling 92 integrated.
During filling-in of the cenlen-t concre-te in-to -the form the lat-terpreferably is vibra-ted for complete Filling o-F the form.
Figs. S to 9 show embodiments of a different type of a platform weighing appara-tus using polymeric concrete as a basic ma-terial4 Whilst this type of platform weighing apparatus may be used For -truck weighing systems in a similar manner as the weighing appa-ratuses according the embodiments of Figs. 1 -to 4 having a plat-form lowered into a pit and flushing with -the ground, the ex-treme low overall height of the apparatus permits applications where the platform weighing apparatus is just put onto the flat ground and wedges are pu-t on either front side o-f the apparatus, Moreover, such type of weighing appara-tus may be used as a self-contained unit for many o-ther applications of platform-scales, f.i. as bath-room scales.
The platform weighing appara-tuses according -to Figs. 5 to 9 distinguish from the embodiments of Figs. 1 to 4 in tha-t -For the platform not only a shuttering or form is of polymeric concrete but -the whole pla-tform is made of this material.
~'75 It should be noted~that these embodiments are shown in Figs. 5 to 9 rather schematically only without showing specific details as the design of the force measuring elements, the support thereof, the specific form of a pit for the platform, the pro-vision of bumpers etc.. These details are known in the art and do not constitute a part of the invention with the exception of specific features explained below.
Fig. 5 schema-tically illustrates a platform 110 essentially made of polymeric concrete, the platform 110 is supported by known force measuring uevices 135,preferably with interposing steel plates 114 and 116,on a base member 112 preferably made of usual concrete or polymeric concre-te.
The platform 110 is of honeycombed design having a ceiling 111 which may be provided with appropriate reinForcernents 118 con-sisting of rods or mats of steel or synthetic material and which overlies. cavities 122 further surrounded by a bottom plate 113 having reinforcements120 embedded therein, outer vertical walls 126 in which the reinforcements 120 are bent upwards and intermediate walls 124 which may be provided with reinforcements as well.
The force measuring devices 130 may be housed in cavities 150 arranged below outer regions of the ceiling 111 and having an open bottom side. These cavities 150 may have the form of longitudinal grooves or their seizes may be limited to a space necessary for housing the force measuring devices 130 at spaced positions in longitudinal direction of the platform 110. Exem-plary four force measuring devices 130 may be housed by cavities 150 arranged at the four edges of the plat-form 110. The cavities 150 may be accessible from the topside through the ceiling 111 which facilitates maintainance and exchange of force measuring devices (Fig. 7).
~ 2~2 with the embodiment of Fig. 5 -the force measuring devices 130 support via plates 140 on a base member 112 which may be formed before insertion oF -t~1e pla-t-form 110 in a corresponding pit by using usual concrete.
Fig. 6 shows an embodiment using the platform 110 of the embodi-ment of Fig. 5 in combination with a base plate 140 made of polymeric concrete. The force measuring devices 130 support on metal plates 138 exemplary fixedly rnoulded via anchorings 136 in the base member 140.
It should be no-ted, t~at there is a tapered or sloped longi-tudinal edge 134 provided at either side of the base member 114 opposed by correspondingly inclined longitudinal edges 132 of exterior longitudinal walls 135 extending downwards from -the ceiling 111 of the platform 110. The circumferential gap formed be-tween -the eclges 132, 134 imparts the platform 110 a certain loose, but limits excess horizontal movements of the platforrn 110 relative to the base member 140.
The base member 1~0 may be provided with suitable reinforcement elements which are arranged in a mould used for moulding or casting of -the base member 140 by using polymeric concrete ma-terial. Due -to the high tensile strength of -the polymeric material the overall weight may be considerably reduced which permits an easy transport and assembly both of -the platform 110 and the base member 140.
As mentioned before, the embodiment according to Fig. 6 is applicable for weighing apparatuses and scales adapted for weighing essentially smaller masses in regions of several kgs or ~-f several hundred kgs ~Jith suc~l applications the thickness of the walls of the platform 110 and the base member 140 may be relatively small and the relnforcement elements may be re-duced in strength or omi-tted a-t all.
~ ~S~2~L
Fig. 7 illus-trates a modi-Fied embodiment of a pla-tform weighing apparatus according to the invention showing the specific design of a platform 150 permi-tting insertion of the force measuring devices 130 from the topside of the platform 150. In this case the cavities 115 for the -Force measuring devices 130 are closed at their topside by steel ~lates 152 casted into the platformand provided with central opening 154 for insertion of a force measuring device 130. A-F-ter insertion o-F the -Force measuring device 130 a cover body 156 is inserted into a recess provided above the steel plate 152 in the platforrn 150, which cover body 156 is secured -to -the steel pla-te 152 preferably by means of screws 158. The cover body 156 exac-tly Fits into the associated opening and flushes at i-ts topside wi-th the top sur-Face of the platForm 150. The cover body 156 may be of metal in particular steel or of polymeric concrete. Such a design permits a replace-ment oF the cover body 156 by a steel insert 160 which may be used for gripping the platform 150 by a crane or the like.
In this connection it should be noted that the platforms 110 and 150 may have any desired shape and size resulting from casting the platforms in appropriate moulds. In par-ticular, further cavities 122 may be provided or these cavities may be subdivided by further horizontal and/or vertical walls. For forming the cavities 122 any measures usable in the field of moulding or casting may be used. Thus, lost and, if desired, self-supporting shutterings or forms made of wood, metal or the like may be used. Alternatively, the cavities may be formed by placing synthetic foam bodies in the mould before moulding. Also, as known in the art of moulding sand approp-riately shaped into -the desired form of the cavities may be used which sand is r~nsed out af-ter moulding. Other foam bodies may consist of material which dissolve upon application o-F
chemical substances,as acids.
Fig. 8 shows a further embodiment of a pla-tform weighing appa-.~, ..
27S;~2 ratus according to the invention where the base member and the platForm are connected by means of a kind o-f parallel lever pair as i-t is commonly used in linkages of mechanical scales.
Such a design permi-ts a unitary cons-truction of a platform/base combina-tion. Exemplary, -the weighing apparatus may have a cir-cular shape comprising a base member 172, a central column 174 supporting just one force measuring device 130 housed in a cavity 175 formed in a platform member 170. The base member 172 is provided with a rim 192 projec-ting upwards and having an increased thickness -two relatively thin walls 184 and 186 extending in parallel and at distance -to each other from said rim 192 radially inwards to a central ring part 188 of the platform member 170, the ring par-t 188 having an increased thick-ness as compared with the thickness of the walls 184, 186 and the thickness of -the platform member 172. As mentioned before, the two -thin walls 18~, 186 function as a parallel lever pair balancing or compensating any assymmetrical loading of the plat-form member 170, as it is well-known in -the field of force measuring. Be-tween the lower wall 1~4 and -the upper surface of the base part 172 there exists a relatively thin gap 178. Simi-larly, there is provided a rela-tively narrow gap 176 between the topside of the wall 186 and the bottom side of the plat-form part 170 parallel there-to. The platform part 170 is pro-vided with cavities 182 similar to the cavities 122 of the embodiment of Fig. 5, however, wi-th smaller height.
In the case when the platform weighing apparatus according to Fig. 8 has a squarelike or rectangular shape, again only one force measuring device 130 may be used arranged a-t the centre of the platform par-t 170 -the parallel lever pair 184, 186 ex--tending both the X- and Y-direction. Alternatively, in the direction of the symmetry axis of the pla-tform part 170 two or several force measuring devices 130 may be arranged in spaced relationship in a direction perpendicular to the paper plane. In this case the parallel lever pair 184/186 will be arranged in a manner and direction only as shown in Fig. 8 ; 1 2~75~2~L
from left to right, i.e. in the direction of the paper plane.
This means that the parallel lever pair may have a limited width in horizontal and/or vertical direction of the paper plane. However, a flat spread or disklike extension results in the advantage that with this embodiment the base part and the platform part may be unitary moulded in one moulding pro-cess and that no further connections are necessary between the the platform part and the base part. Alternatively, the platform part could be horizontally seperated from the base part approximately in the height of the gap 176.
It should be noted,that when casting or moulding the platform and the base member various elements, bearing and connection parts, linkages and so on may be embedded in the polymeric concrete.This is true for electrical elements and the force measuring devices which may be enclosed partially in total.
Force measuring devices applicable are exemplary those dis-closed in the European Patent Application Publication 145001.
Fig. 9 shows another embodime-nt of a platform weighing appa-ratus which may be applicable for quite different measuring ranges in the order of a few kgs up to the order of several tons. With this embodiment the platform weighing apparatus is a freestanding unit manufactured in a plant and easily trans-ported to any operational site. Exemplary, such an apparatus may be used as a wheel load weighing device for trucks, one device each being provided for the wheels of one or more truck axles. In this case, the relatively flat unit with an overall height between 20 and 50 mms may be lowered into the road or may be provided preferably at either front side with a driving-up and driving-down ramp indicatea a-t 198 in Fig. 9.
With this embodiment the base member 190 is provided at least laterally to the driving direction with a side wall part 94 which is provided, depending on the stability requirements, with i ~Sl;~
cavities 195. The side wall 194 preferably has a circumferential extension, the outer shape o-f -the appara~.us being of rectangular shape. A platform 180 supports through -force measuring devices 130 on -the bo-ttom 191 of the base member 190. As a modification in respect of embodiments explained before the pla-tform 180 is provided with cavities 197 in -the regions above the force measuring devices 130 which cavities have a lower height, The central part of the pla-tform 180 extends further downwards and has large cavities 193. This design gives an improved stability to the platform. :
An important feature of the ernbodiment of Fig. 9 is the type of tight sealing o-f the circumferential gap between the exterior peripheral surface of the platform 180 and the interior peri-pheral surface of the rim 194. For this purpose elastomeric material 196 is filled into said gap which preferably is widened in its upper region. The strongly adhering elastomeric material 196 transmits any lateral forces acting onto the platform 180 to the base member 190. Furthermore, it functions as a bumper limiting any horizontal movement of -the platform 180.
It should be noted, that the polymeric concrete used for pro-duction of the platform and the base member is that used in connection with the embodiments of Figs. 1 to 4. This is true for the methods of producing these elements as well.
Even if the base frame 34 and the pit is produced in the usual way there are s-till advantages in using a pre-produced lost self-supporting form consis-ting of polymeric concre-te. Independently, the provision and clamping of the cover strip 60 is of importance for the platform weighing apparatus according to the invention, serving both as a sealing and as a bumper. Also, inserting the force measuring element from the top of the platform is extremely useful, since it does no more require any access to the space below the platform 10 resulting in an ex-tremely fla-t arrangement with an overall height in the order of 200 to 500 mms.
I-t should be noted, that the cover strip 60 replaces the complex .
S~2~.
mechanical linkage between the platform 10 and base frame 34 which again contributes to the reduction of -the overall height of the apparatus. Method step 7 indicated above enables the transport of -the base frame 34 having inserted thereto the form 12 clamped to the base frame 34 by the cover strip 60 as a unit.
The platform 10 may then be formed by filling usual concrete in-to the form 12 simultaneously with fixing the base frame 3~ into the pit by filling any spaces therebetween with lean conc~ete 40.
The cover strip 60 advantageously prevents any penetration of concrete into the peripheral gap 52.
The material called ~polymeric concrete" before is also known as polymeric casting material. In this connection it is referred to the firm publication KID-INF0 K.I.D. Impragniertechnik GmbH, Georgenstrasse 8, D-8018 Grafing, West-Germany. Polymeric syn-thetic materials which may be used for polymeric concrete are exemplary epoxy resirls (EP)s m~tl1yl-1etacry1a~e (,~1ilA) resin and unsaturated polyester resin (UP) or mixtures thereof.
Filler materials are prefereably quartz or chalk powders, quartzite or crushed granite. Furthermore, glassor preferably carbon fibres may be use. Also, other filler materials may be used as long as they do not undergo any essential chemical reaction with the resin and as long they are dry. It should be noted,~that the resins used for the polymeric concrete harden at ambient tempe-ratures. The hardening is initiated by suitable known agents and is completed in a time range between a few minutes and several t , hours. Since the method of providing moulds for moulding and casting polymeric synthetic material containing filler materials for the production of polymeric concrete is very similar to the preparation of forms for metal casting many measures used in the latter field are applicable for casting polymeriG concrete with the additional advantage of hardening at ambient temperatures, such that considerations of high temperatures are eliminated.
Polymeric concrete may be provided with appropriate reinforcements which may project above the surface of the polymeric concrete into ~ ~7S~
the interior of the form 12 Fig. 4 shows an embodimen-t o-f the platform weighing apparatus according -to the inven-tion wi-th the improvement tha-t in addi-tion -the -the base frame and the form 12 a sealing ~is in-tegrated into the form 12 again made of polymeric concre-te. This resul-ts in an increased s-tiffness of the form and a highly resistant pavemen-t against chemical and mechanical influences. The cement concre-te is filled-in through openings 92 whils-t further open-ings 94 spaced from the openings 92 and having preferably a smaller diameter serve as air ou-tlets and for monitoring the complete filling of -the form with concrete. Wi-th such a ceiling 92 no fine -treatment of -the top surface of the platform is necessary and -the shape of the platform is exactly defined by the form having the ceiling 92 integrated.
During filling-in of the cenlen-t concre-te in-to -the form the lat-terpreferably is vibra-ted for complete Filling o-F the form.
Figs. S to 9 show embodiments of a different type of a platform weighing appara-tus using polymeric concrete as a basic ma-terial4 Whilst this type of platform weighing apparatus may be used For -truck weighing systems in a similar manner as the weighing appa-ratuses according the embodiments of Figs. 1 -to 4 having a plat-form lowered into a pit and flushing with -the ground, the ex-treme low overall height of the apparatus permits applications where the platform weighing apparatus is just put onto the flat ground and wedges are pu-t on either front side o-f the apparatus, Moreover, such type of weighing appara-tus may be used as a self-contained unit for many o-ther applications of platform-scales, f.i. as bath-room scales.
The platform weighing appara-tuses according -to Figs. 5 to 9 distinguish from the embodiments of Figs. 1 to 4 in tha-t -For the platform not only a shuttering or form is of polymeric concrete but -the whole pla-tform is made of this material.
~'75 It should be noted~that these embodiments are shown in Figs. 5 to 9 rather schematically only without showing specific details as the design of the force measuring elements, the support thereof, the specific form of a pit for the platform, the pro-vision of bumpers etc.. These details are known in the art and do not constitute a part of the invention with the exception of specific features explained below.
Fig. 5 schema-tically illustrates a platform 110 essentially made of polymeric concrete, the platform 110 is supported by known force measuring uevices 135,preferably with interposing steel plates 114 and 116,on a base member 112 preferably made of usual concrete or polymeric concre-te.
The platform 110 is of honeycombed design having a ceiling 111 which may be provided with appropriate reinForcernents 118 con-sisting of rods or mats of steel or synthetic material and which overlies. cavities 122 further surrounded by a bottom plate 113 having reinforcements120 embedded therein, outer vertical walls 126 in which the reinforcements 120 are bent upwards and intermediate walls 124 which may be provided with reinforcements as well.
The force measuring devices 130 may be housed in cavities 150 arranged below outer regions of the ceiling 111 and having an open bottom side. These cavities 150 may have the form of longitudinal grooves or their seizes may be limited to a space necessary for housing the force measuring devices 130 at spaced positions in longitudinal direction of the platform 110. Exem-plary four force measuring devices 130 may be housed by cavities 150 arranged at the four edges of the plat-form 110. The cavities 150 may be accessible from the topside through the ceiling 111 which facilitates maintainance and exchange of force measuring devices (Fig. 7).
~ 2~2 with the embodiment of Fig. 5 -the force measuring devices 130 support via plates 140 on a base member 112 which may be formed before insertion oF -t~1e pla-t-form 110 in a corresponding pit by using usual concrete.
Fig. 6 shows an embodiment using the platform 110 of the embodi-ment of Fig. 5 in combination with a base plate 140 made of polymeric concrete. The force measuring devices 130 support on metal plates 138 exemplary fixedly rnoulded via anchorings 136 in the base member 140.
It should be no-ted, t~at there is a tapered or sloped longi-tudinal edge 134 provided at either side of the base member 114 opposed by correspondingly inclined longitudinal edges 132 of exterior longitudinal walls 135 extending downwards from -the ceiling 111 of the platform 110. The circumferential gap formed be-tween -the eclges 132, 134 imparts the platform 110 a certain loose, but limits excess horizontal movements of the platforrn 110 relative to the base member 140.
The base member 1~0 may be provided with suitable reinforcement elements which are arranged in a mould used for moulding or casting of -the base member 140 by using polymeric concrete ma-terial. Due -to the high tensile strength of -the polymeric material the overall weight may be considerably reduced which permits an easy transport and assembly both of -the platform 110 and the base member 140.
As mentioned before, the embodiment according to Fig. 6 is applicable for weighing apparatuses and scales adapted for weighing essentially smaller masses in regions of several kgs or ~-f several hundred kgs ~Jith suc~l applications the thickness of the walls of the platform 110 and the base member 140 may be relatively small and the relnforcement elements may be re-duced in strength or omi-tted a-t all.
~ ~S~2~L
Fig. 7 illus-trates a modi-Fied embodiment of a pla-tform weighing apparatus according to the invention showing the specific design of a platform 150 permi-tting insertion of the force measuring devices 130 from the topside of the platform 150. In this case the cavities 115 for the -Force measuring devices 130 are closed at their topside by steel ~lates 152 casted into the platformand provided with central opening 154 for insertion of a force measuring device 130. A-F-ter insertion o-F the -Force measuring device 130 a cover body 156 is inserted into a recess provided above the steel plate 152 in the platforrn 150, which cover body 156 is secured -to -the steel pla-te 152 preferably by means of screws 158. The cover body 156 exac-tly Fits into the associated opening and flushes at i-ts topside wi-th the top sur-Face of the platForm 150. The cover body 156 may be of metal in particular steel or of polymeric concrete. Such a design permits a replace-ment oF the cover body 156 by a steel insert 160 which may be used for gripping the platform 150 by a crane or the like.
In this connection it should be noted that the platforms 110 and 150 may have any desired shape and size resulting from casting the platforms in appropriate moulds. In par-ticular, further cavities 122 may be provided or these cavities may be subdivided by further horizontal and/or vertical walls. For forming the cavities 122 any measures usable in the field of moulding or casting may be used. Thus, lost and, if desired, self-supporting shutterings or forms made of wood, metal or the like may be used. Alternatively, the cavities may be formed by placing synthetic foam bodies in the mould before moulding. Also, as known in the art of moulding sand approp-riately shaped into -the desired form of the cavities may be used which sand is r~nsed out af-ter moulding. Other foam bodies may consist of material which dissolve upon application o-F
chemical substances,as acids.
Fig. 8 shows a further embodiment of a pla-tform weighing appa-.~, ..
27S;~2 ratus according to the invention where the base member and the platForm are connected by means of a kind o-f parallel lever pair as i-t is commonly used in linkages of mechanical scales.
Such a design permi-ts a unitary cons-truction of a platform/base combina-tion. Exemplary, -the weighing apparatus may have a cir-cular shape comprising a base member 172, a central column 174 supporting just one force measuring device 130 housed in a cavity 175 formed in a platform member 170. The base member 172 is provided with a rim 192 projec-ting upwards and having an increased thickness -two relatively thin walls 184 and 186 extending in parallel and at distance -to each other from said rim 192 radially inwards to a central ring part 188 of the platform member 170, the ring par-t 188 having an increased thick-ness as compared with the thickness of the walls 184, 186 and the thickness of -the platform member 172. As mentioned before, the two -thin walls 18~, 186 function as a parallel lever pair balancing or compensating any assymmetrical loading of the plat-form member 170, as it is well-known in -the field of force measuring. Be-tween the lower wall 1~4 and -the upper surface of the base part 172 there exists a relatively thin gap 178. Simi-larly, there is provided a rela-tively narrow gap 176 between the topside of the wall 186 and the bottom side of the plat-form part 170 parallel there-to. The platform part 170 is pro-vided with cavities 182 similar to the cavities 122 of the embodiment of Fig. 5, however, wi-th smaller height.
In the case when the platform weighing apparatus according to Fig. 8 has a squarelike or rectangular shape, again only one force measuring device 130 may be used arranged a-t the centre of the platform par-t 170 -the parallel lever pair 184, 186 ex--tending both the X- and Y-direction. Alternatively, in the direction of the symmetry axis of the pla-tform part 170 two or several force measuring devices 130 may be arranged in spaced relationship in a direction perpendicular to the paper plane. In this case the parallel lever pair 184/186 will be arranged in a manner and direction only as shown in Fig. 8 ; 1 2~75~2~L
from left to right, i.e. in the direction of the paper plane.
This means that the parallel lever pair may have a limited width in horizontal and/or vertical direction of the paper plane. However, a flat spread or disklike extension results in the advantage that with this embodiment the base part and the platform part may be unitary moulded in one moulding pro-cess and that no further connections are necessary between the the platform part and the base part. Alternatively, the platform part could be horizontally seperated from the base part approximately in the height of the gap 176.
It should be noted,that when casting or moulding the platform and the base member various elements, bearing and connection parts, linkages and so on may be embedded in the polymeric concrete.This is true for electrical elements and the force measuring devices which may be enclosed partially in total.
Force measuring devices applicable are exemplary those dis-closed in the European Patent Application Publication 145001.
Fig. 9 shows another embodime-nt of a platform weighing appa-ratus which may be applicable for quite different measuring ranges in the order of a few kgs up to the order of several tons. With this embodiment the platform weighing apparatus is a freestanding unit manufactured in a plant and easily trans-ported to any operational site. Exemplary, such an apparatus may be used as a wheel load weighing device for trucks, one device each being provided for the wheels of one or more truck axles. In this case, the relatively flat unit with an overall height between 20 and 50 mms may be lowered into the road or may be provided preferably at either front side with a driving-up and driving-down ramp indicatea a-t 198 in Fig. 9.
With this embodiment the base member 190 is provided at least laterally to the driving direction with a side wall part 94 which is provided, depending on the stability requirements, with i ~Sl;~
cavities 195. The side wall 194 preferably has a circumferential extension, the outer shape o-f -the appara~.us being of rectangular shape. A platform 180 supports through -force measuring devices 130 on -the bo-ttom 191 of the base member 190. As a modification in respect of embodiments explained before the pla-tform 180 is provided with cavities 197 in -the regions above the force measuring devices 130 which cavities have a lower height, The central part of the pla-tform 180 extends further downwards and has large cavities 193. This design gives an improved stability to the platform. :
An important feature of the ernbodiment of Fig. 9 is the type of tight sealing o-f the circumferential gap between the exterior peripheral surface of the platform 180 and the interior peri-pheral surface of the rim 194. For this purpose elastomeric material 196 is filled into said gap which preferably is widened in its upper region. The strongly adhering elastomeric material 196 transmits any lateral forces acting onto the platform 180 to the base member 190. Furthermore, it functions as a bumper limiting any horizontal movement of -the platform 180.
It should be noted, that the polymeric concrete used for pro-duction of the platform and the base member is that used in connection with the embodiments of Figs. 1 to 4. This is true for the methods of producing these elements as well.
Claims (41)
1. A heavy duty weighing apparatus for trucks, equipment and the like including a platform mountable in a ground pit on force measuring elements resting on concrete support means, the platform comprising:
a lost self-supporting shuttering pre-fabricated of poly-meric concrete filled, at an operational site, with cement concrete.
a lost self-supporting shuttering pre-fabricated of poly-meric concrete filled, at an operational site, with cement concrete.
2. The apparatus of claim 1, wherein said shuttering includes a ceiling wall made of polymeric concrete a top side there-of constituting a load receiving surface of said platform.
3. The apparatus of claim 2, wherein said ceiling wall is pre-fabricated unitary with said shuttering.
4. The apparatus of claim 2, wherein said ceiling wall is pro-vided with at least one opening for filling in said cement concrete.
5. The apparatus of claim 4, wherein said ceiling wall is pro-vided with at least one hole arranged in spaced relation-ship to said at least on opening for permitting escape of air contained in said shuttering and observation of said filling-in of said cement concrete.
6. The apparatus of claim 1 further comprising:
a supporting base frame pre-fabricated of polymeric concrete and insertable in said ground pit for accommodating said platform therein, a load receiving surface of said platform essentially flushing with an essentially horizontal top face surface of said base frame, said base frame having lower horizontal sections extending inwards for supporting said force measuring elements.
a supporting base frame pre-fabricated of polymeric concrete and insertable in said ground pit for accommodating said platform therein, a load receiving surface of said platform essentially flushing with an essentially horizontal top face surface of said base frame, said base frame having lower horizontal sections extending inwards for supporting said force measuring elements.
7. The apparatus of claim 6, wherein said lower horizontal sections have inner edges bent downwards.
8. The apparatus of claim 6, wherein said base frame opens in upward direction by having sidewalls inclined to the hori-zontal, said platform having side walls essentially corre-spondingly inclined to the horizontal.
9. The apparatus of claim 6, wherein said polymeric concrete of said base frame has reinforcement means embedded.
10. The apparatus of claim 6, wherein said base frame is con-creted into said ground pit.
11. The apparatus of claim 1 wherein a bottom of said ground pit is covered by a thin smooth layer of cement concrete.
12. The apparatus of claim 1 wherein said shuttering has formed therein vertical centrally hollow columns extending to a top surface of said platform, said columns having fixedly em-bedded receptacles for housing said force measuring elements insertable to said receptecles from said top surface.
13. The apparatus of claim 12, wherein said receptacles are made of steel and have an essentially cylindrical form, and have extended rings at their upper ends for receiving support-ing plates for said force measuring elements.
14. The apparatus of claim 12, wherein said receptacles are made of steel and have a frustro-conical form narrowing upwards, top ends of said receptacles being formed as extended rings for receiving supporting plates for said force measuring elements.
15. The apparatus of claim 6, wherein a peripheral upper edge of said platform is firmly connected to said horizontal face surface of said base frame by a cover strip made of elasto-meric material and bridging a gap formed between said plat-form and said base frame, said cover strip acting as a means for limiting lateral movements of said platform rela-tive to said base frame and for transmitting any lateral forces introduced to said platform to said base frame.
16. The apparatus of claim 1, wherein for extraordinary long platforms said shuttering is divided into a plurality of modules having steplike face edges for putting said modules together, elastomeric material being interposed between opposing face edges.
17. A heavy duty weighing apparatus including a platform mount-able in a ground pit and comprising a base frame insertable into said ground pit for loosely acommodating said platform, said base frame being pre-fabricated of polymeric concrete and having an essentially horizontal top face surface flush-ing with a force receiving surface of said platform and lower horizontal sections extending inwards in said ground pit for supporting force measuring elements on which said platform rests.
18. A method of manufacturing a heavy duty platform weighing apparatus comprising the steps:
pre-fabricating a shuttering for said platform by mould-ing of polymeric concrete material at a manufacturing site;
transporting said shuttering to an operational site; and connecting said platform by filling said shuttering with cement concrete.
pre-fabricating a shuttering for said platform by mould-ing of polymeric concrete material at a manufacturing site;
transporting said shuttering to an operational site; and connecting said platform by filling said shuttering with cement concrete.
19. The method of claim 18 further comprising:
the step of placing said shuttering into said ground bit before filling-in of cement concrete into said shuttering.
the step of placing said shuttering into said ground bit before filling-in of cement concrete into said shuttering.
20. The method of claim 18 further comprising the steps of pre-fabricating a base frame by moulding thereof of poly-meric concrete at a manufacturing site;
transportiny said pre-fabricated base frame to said oper-ational site; and securing said base frame in said ground pit by concreting said base frame therein.
transportiny said pre-fabricated base frame to said oper-ational site; and securing said base frame in said ground pit by concreting said base frame therein.
21. Method of claim 20 wherein said shuttering is placed into said base frame and secured thereto at said manufacturing site before transporting thereof together to said oper-ational site.
22. The method of claim 21 wherein said shuttering is secured to said base frame by fixing a cover strip of elastomeric material circumferentially both to said base frame and said shuttering.
23. The method of claim 18 further comprising the step of inserting force measuring cells into receptacles formed in said shuttering from a top side of said platform after pro-ducing thereof.
24. A platform weighing apparatus comprising:
a platform structured by including cavities and pre-fab-ricated of polymeric concrete by moulding;
a base means; and force measuring elements arranged between said platform and said base means.
a platform structured by including cavities and pre-fab-ricated of polymeric concrete by moulding;
a base means; and force measuring elements arranged between said platform and said base means.
25. The apparatus of claim 24, wherein said base means is pre-fabricated of polymeric concrete by moulding.
26. The apparatus of claim 24, wherein said force measuring elements are housed in recesses provided in said platform said recesses being open at least in downward direct-ion.
27. The apparatus of claim 26, wherein said recesses are accessible through openings provided at a top surface of said platform.
28. The apparatus of claim 27, wherein said recesses are separated from said openings by annular plates embedded in said platform, said plates having apertures adapted for inserting said force measuring elements, said apertures being closed by inserts adapted to be placed into said openings and fixed to said steel plates, the top surfaces of said inserts essentially flushing with a top surface of said platform.
29. The apparatus of claim 24, wherein at least part of a circumferential lower edge of said platform and of a peri-pheral edge of said base means are provided with comple-mentary opposing spaced surfaces for limiting any lateral movement of said platform in respect of said base means.
30. The apparatus of claim 24, wherein said platform and said base means are formed unitary of polymeric concrete a parallel lever pair means extending horizontally from a central rigid vertical support means outwards to a side wall of said base means, said support means resting on at least one centrally arranged said force measuring element housed in a recess thereof and having formed at an upper region thereof said platform in horizontal extension.
31. The apparatus of claim 30 wherein only one said force measur-ing element is arranged in a center of said platform.
32. The arrangement of claim 30, wherein at least two said force measuring elements are arranged in spaced relationship along a symmetry axis of said platform.
33. The apparatus of claim 30, wherein said platform has a circular shape, said parallel lever pair means consists of two spaced thin walls extending horizontally in parallel and wherein said platform has a lower circumferential edge and said side wall of said base means has an upper circum-ferential edge each at least partially provided with com-plementary opposing slanted surfaces.
34. A method for manufacturing a platform weighing apparatus com-prising the steps:
preparing a mould according to the outer contours of a plat-form at a manufacturing site;
placing form bodies into said mould corresponding to cavities to be formed in said platform;
moulding said platform by filling-in of polymeric concrete into said mould; and removing said platform after solidification of said poly-meric concrete from said mould.
preparing a mould according to the outer contours of a plat-form at a manufacturing site;
placing form bodies into said mould corresponding to cavities to be formed in said platform;
moulding said platform by filling-in of polymeric concrete into said mould; and removing said platform after solidification of said poly-meric concrete from said mould.
35. The method of claim 34, wherein said form bodies are at least formed as lost shuttering elements.
36. The method of claim 34, wherein said form bodies are made of synthetic foam material.
37. The method of claim 34, wherein said form bodies are made of removable material which is removed from said finished plat-form.
38. The method of claim 34, wherein a base means for supporting said platform is moulded of polymeric concrete.
39. The method of claim 38, wherein said base means is moulded integrally with said platform.
40. The method of claim 34, wherein form bodies are placed in-to said mould for forming recesses for accommodating force measuring elements, said recesses opening downwards and having openings at a top surface of said platform and further comprising the steps of inserting said force measuring cells from said top surface of said platform into said recesses and closing said openings.
41. The method of claim 34 further comprising the step of placing reinforcement means into said mould before filling-in polymeric concrete.
Applications Claiming Priority (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19863604421 DE3604421A1 (en) | 1986-02-13 | 1986-02-13 | Road-vehicle balance and process for producing it |
| DEP3604421.0 | 1986-02-13 | ||
| DE19863604419 DE3604419A1 (en) | 1986-02-13 | 1986-02-13 | Platform balance |
| DEP3604419.9 | 1986-02-13 | ||
| DE19863611095 DE3611095A1 (en) | 1986-02-13 | 1986-04-03 | Balance for road vehicles |
| DEP3611095.7 | 1986-04-03 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1275121A true CA1275121A (en) | 1990-10-09 |
Family
ID=27194003
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000529539A Expired - Fee Related CA1275121A (en) | 1986-02-13 | 1987-02-12 | Platform weighing apparatus and method for producing thereof |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US4832140A (en) |
| EP (1) | EP0232909B1 (en) |
| CA (1) | CA1275121A (en) |
| DE (1) | DE3763252D1 (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ATE84612T1 (en) * | 1988-05-18 | 1993-01-15 | Kistler Instrumente Ag | LOAD TRANSDUCERS FOR INSTALLATION IN MEASURING PLATFORMS. |
| US4979581A (en) * | 1988-05-27 | 1990-12-25 | Kroll William P | Low profile wheel scale assembly |
| US5446248A (en) * | 1992-11-12 | 1995-08-29 | First-Weigh Manufacturing, Inc. | Center-lock portable truck scale |
| DK200000211U3 (en) * | 2000-06-20 | 2001-09-28 | Eriksen Knud Lund | Plate for bridge weight |
| CN1119632C (en) * | 2000-09-02 | 2003-08-27 | 乔爱良 | Mobile vehicle overrunning detection station |
| CN1373327A (en) * | 2001-03-01 | 2002-10-09 | 俞天平 | Active wind regulating valve |
| AT11656U1 (en) * | 2010-03-09 | 2011-02-15 | Hottinger Messtechnik Baldwin | MEASURING ARRANGEMENT FOR DETECTING STATIC AND / OR DYNAMIC LOADING OF A TRACK |
| US20150051514A1 (en) * | 2013-08-15 | 2015-02-19 | Safety in Motion, Inc. | Concussion/balance evaluation system and method |
| CN114375238A (en) * | 2019-09-13 | 2022-04-19 | 施耐博格矿物技术股份有限公司 | Structural component for machine tool and manufacturing method thereof |
Family Cites Families (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE8113100U1 (en) * | 1981-10-29 | Koblischek, Peter, 6000 Frankfurt | Machine stand | |
| GB446122A (en) * | 1935-01-23 | 1936-04-24 | Avery Ltd W & T | Improvements relating to platform weighing machines or weighbridges |
| GB1239248A (en) * | 1968-10-24 | 1971-07-14 | ||
| FR2027506A1 (en) * | 1969-01-09 | 1970-10-02 | Philips Ind Commerciale | |
| SE368087B (en) * | 1971-09-14 | 1974-06-17 | Transcale Ab | |
| DE2263145C3 (en) * | 1972-12-22 | 1978-04-06 | Pietzsch, Ludwig, Dr.-Ing., 7500 Karlsruhe | Measuring transducers for wheel or axle loads of road vehicles |
| DE2439266A1 (en) * | 1974-08-16 | 1976-02-26 | Pfister Waagen Gmbh | Rail guided vehicle weighbridge - has reinforced concrete platform using lost shuttering to save time during construction |
| CH612610A5 (en) * | 1976-03-23 | 1979-08-15 | Studer Ag Fritz | Machine stand for machine tools |
| US4177868A (en) * | 1978-01-30 | 1979-12-11 | Bio-Dynamics Inc. | Weight-measuring and display device |
| US4333543A (en) * | 1979-04-11 | 1982-06-08 | Ludwig Pietzsch | Wheel or axle load measuring device for road vehicles |
| US4266624A (en) * | 1979-07-13 | 1981-05-12 | Masstron Scale, Inc. | Weighing apparatus |
| DE3030914C2 (en) * | 1980-08-16 | 1989-08-10 | Peter 6000 Frankfurt Koblischek | Process for the production of machine frames using polymer concrete |
| DE8021861U1 (en) * | 1980-08-16 | 1982-01-21 | Koblischek, Peter, 6000 Frankfurt | Machine stand |
| US4339010A (en) * | 1981-01-02 | 1982-07-13 | Malikov Georgy F | Apparatus for weighing transport vehicles in motion |
| US4392537A (en) * | 1981-06-15 | 1983-07-12 | Ab Bofors Elektronik | Weighbridge and method of producing it |
| EP0097734A1 (en) * | 1982-06-30 | 1984-01-11 | Carl Schenck Ag | Process for the manufacture of a balance for road vehicles, and mould for carrying out the process |
| GB2125175B (en) * | 1982-08-11 | 1985-08-29 | Avery Ltd W & T | Weighbridges |
| SE436601B (en) * | 1982-08-25 | 1985-01-07 | Flintab Vaagsystem Ab | WEIGHING DEVICE WITH A PLATFORM INTENDED TO PICK UP A LOAD, EXTRA A VEHICLE |
| DE3275867D1 (en) * | 1982-11-09 | 1987-04-30 | Schenck Ag Carl | Process for manufacturing a weigh bridge and assembly unit with a load cell, especially for use in carrying out the process |
| DE3604420A1 (en) * | 1986-01-24 | 1987-08-20 | Pfister Gmbh | Large-area force-measuring appliance |
| US4572308A (en) * | 1984-05-07 | 1986-02-25 | Firma Carl Schenck Ag | Method for constructing a weighbridge and weighing cell assembly, in particular for use in performing the method |
| US4549962A (en) * | 1984-07-19 | 1985-10-29 | Envirex Inc. | Rotating biological contactor |
-
1987
- 1987-02-11 EP EP87101905A patent/EP0232909B1/en not_active Expired - Lifetime
- 1987-02-11 DE DE8787101905T patent/DE3763252D1/en not_active Expired - Fee Related
- 1987-02-12 CA CA000529539A patent/CA1275121A/en not_active Expired - Fee Related
-
1988
- 1988-10-07 US US07/253,922 patent/US4832140A/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| EP0232909A3 (en) | 1988-07-06 |
| US4832140A (en) | 1989-05-23 |
| EP0232909B1 (en) | 1990-06-13 |
| EP0232909A2 (en) | 1987-08-19 |
| DE3763252D1 (en) | 1990-07-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1275121A (en) | Platform weighing apparatus and method for producing thereof | |
| US3935914A (en) | Vehicle platform scale | |
| FI71995B (en) | VAOG | |
| US20110266073A1 (en) | Modular weighbridge | |
| US2962275A (en) | Platform weighting apparatus | |
| KR20130056372A (en) | Reinforced concrete measuring platform and method of forming the concrete | |
| US3727707A (en) | Concrete pit and deck construction for platform scales and method of making the same | |
| EP2554957A1 (en) | Weighbridge component | |
| CA1274258A (en) | Flat-spread force measuring device | |
| US4733736A (en) | Load cell assembly | |
| US4572308A (en) | Method for constructing a weighbridge and weighing cell assembly, in particular for use in performing the method | |
| CA1130325A (en) | Continuous slab weighbridge device | |
| CN210953063U (en) | Weighing platform structure | |
| RU2263288C2 (en) | Platform balance for weighing vehicles | |
| CA1308747C (en) | Scale assembly | |
| CN201104269Y (en) | Weighing bridge | |
| US5748690A (en) | Construction method of nuclear reactor reinforced concrete containment vessel and diaphragm floor structure of nuclear reactor reinforced concrete containment vessel | |
| US4874050A (en) | Portable deck truck scale | |
| WO1991019960A1 (en) | Weighing apparatus | |
| KR101035367B1 (en) | Ground Stationary Type Scale Using Concrete Supportor and Ironware Frame | |
| KR200451669Y1 (en) | Weight Scale For Vehicles Using A Concrete Supportor and A Number of Sensing Plates | |
| JPS60102526A (en) | Detecting apparatus for axle load of transport vehicle | |
| CN112393789B (en) | Module for multi-module weighing applications | |
| EP3779377B1 (en) | Modules for multi-module weighing applications | |
| CN111829630B (en) | Manufacturing method of dynamic truck scale and road installation method of dynamic truck scale |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |